Thermal comfort in naturally ventilated buildings with double skin façade under tropical climate conditions: The influence of key design parameters

This paper evaluates the influence of key design parameters on the thermal behaviour of a naturally ventilated building with Double Skin Façade (DSF) under tropical climate conditions. Using a reference model of a conventional office building in the city of Rio de Janeiro and two groups of design parameters, dynamic thermal simulations are systematically applied to optimize design options with the aim to maximize the annual acceptable thermal comfort levels within the occupied spaces. This study not only defines the dimensional parameters to maximize the system airflows, but also investigates the significance of design decisions such as thermal mass and shading devices on the system performance. Options to avoid unintentional reverse flow on the upper floors and maintenance of balanced horizontal airflow rates across the floors are also addressed. Two optimized naturally ventilated building models with DSF are developed and evaluated in terms of thermal performance. Results show that acceptable thermal comfort levels can be met for nearly 70% of the occupied hours. Although the office building will still require other means of cooling during peak summer periods, the incorporation of DSF as part of a mixed-mode ventilation strategy can potentially have a significant impact on annual energy consumption.